1. Field of the Invention
This invention relates generally to electric safety connectors and in particular to such connectors which connect power to exposed terminals only after the parts of the connector are properly coupled.
2. Prior Art
It is well known that electric tapping sockets, as used in various applications, constitute a safety hazard in that improper contact therewith or connection thereto can cause a danger of electrocution. This hazard is particularly dangerous in domestic applications as young children, in their curiosity, can push items which may be electrically conductive, such as scissors or needles, into the common wall socket. In other uses, such as commercial and industrial, improper maintenance or care may also cause a danger of electrocution.
In response to these hazards, various attempts have been made to limit the danger of electrocution. One attempt includes a tapping socket having means for obturating the orifices of the socket. Normally the obturating means cannot be retracted unless the plugs of the corresponding connecting element are simultaneously introduced into the orifices. Unfortunately, with repeated use and the passage of time the obturating means often fail to operate properly and thereby loose their desired safety characteristics.
Another apparatus for reducing the danger of electrocution automatically interrupts power to the tapping socket when an improper grounding load is sensed at the connection terminals. Unfortunately this apparatus is complex in construction and high in cost making it unduely burdensome for small applications and domestic use.
Still another type of safety connector only connects power to the exposed terminals of the tapping socket after the two parts of the plug have been properly connected. This type normally includes a tapping socket having a pup jack or tip jack and a movable member mounted within the socket for connecting power to the jack. When the corresponding plug assembly is properly coupled to the tapping socket, a magnetic actuator moves the movable member from a safety position to a working position to connect power to the jack. When the plug assembly is removed from the socket, elastic biasing means returns the movable member to the safety position thereby disconnecting power from the jack. Unfortunately, this type of connector suffers from the problem that the elastic biasing means tends to fatigue with usage and age resulting in reduced effectiveness and eventually a total failure of the safety disconnect function.